1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /******************************************************************************
3  *
4  * Module Name: evregion - Operation Region support
5  *
6  * Copyright (C) 2000 - 2023, Intel Corp.
7  *
8  *****************************************************************************/
9 
10 #include <acpi/acpi.h>
11 #include "accommon.h"
12 #include "acevents.h"
13 #include "acnamesp.h"
14 #include "acinterp.h"
15 
16 #define _COMPONENT          ACPI_EVENTS
17 ACPI_MODULE_NAME("evregion")
18 
19 extern u8 acpi_gbl_default_address_spaces[];
20 
21 /* Local prototypes */
22 
23 static void
24 acpi_ev_execute_orphan_reg_method(struct acpi_namespace_node *device_node,
25 				  acpi_adr_space_type space_id);
26 
27 static acpi_status
28 acpi_ev_reg_run(acpi_handle obj_handle,
29 		u32 level, void *context, void **return_value);
30 
31 /*******************************************************************************
32  *
33  * FUNCTION:    acpi_ev_initialize_op_regions
34  *
35  * PARAMETERS:  None
36  *
37  * RETURN:      Status
38  *
39  * DESCRIPTION: Execute _REG methods for all Operation Regions that have
40  *              an installed default region handler.
41  *
42  ******************************************************************************/
43 
acpi_ev_initialize_op_regions(void)44 acpi_status acpi_ev_initialize_op_regions(void)
45 {
46 	acpi_status status;
47 	u32 i;
48 
49 	ACPI_FUNCTION_TRACE(ev_initialize_op_regions);
50 
51 	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
52 	if (ACPI_FAILURE(status)) {
53 		return_ACPI_STATUS(status);
54 	}
55 
56 	/* Run the _REG methods for op_regions in each default address space */
57 
58 	for (i = 0; i < ACPI_NUM_DEFAULT_SPACES; i++) {
59 		/*
60 		 * Make sure the installed handler is the DEFAULT handler. If not the
61 		 * default, the _REG methods will have already been run (when the
62 		 * handler was installed)
63 		 */
64 		if (acpi_ev_has_default_handler(acpi_gbl_root_node,
65 						acpi_gbl_default_address_spaces
66 						[i])) {
67 			acpi_ev_execute_reg_methods(acpi_gbl_root_node,
68 						    acpi_gbl_default_address_spaces
69 						    [i], ACPI_REG_CONNECT);
70 		}
71 	}
72 
73 	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
74 	return_ACPI_STATUS(status);
75 }
76 
77 /*******************************************************************************
78  *
79  * FUNCTION:    acpi_ev_address_space_dispatch
80  *
81  * PARAMETERS:  region_obj          - Internal region object
82  *              field_obj           - Corresponding field. Can be NULL.
83  *              function            - Read or Write operation
84  *              region_offset       - Where in the region to read or write
85  *              bit_width           - Field width in bits (8, 16, 32, or 64)
86  *              value               - Pointer to in or out value, must be
87  *                                    a full 64-bit integer
88  *
89  * RETURN:      Status
90  *
91  * DESCRIPTION: Dispatch an address space or operation region access to
92  *              a previously installed handler.
93  *
94  * NOTE: During early initialization, we always install the default region
95  * handlers for Memory, I/O and PCI_Config. This ensures that these operation
96  * region address spaces are always available as per the ACPI specification.
97  * This is especially needed in order to support the execution of
98  * module-level AML code during loading of the ACPI tables.
99  *
100  ******************************************************************************/
101 
102 acpi_status
acpi_ev_address_space_dispatch(union acpi_operand_object * region_obj,union acpi_operand_object * field_obj,u32 function,u32 region_offset,u32 bit_width,u64 * value)103 acpi_ev_address_space_dispatch(union acpi_operand_object *region_obj,
104 			       union acpi_operand_object *field_obj,
105 			       u32 function,
106 			       u32 region_offset, u32 bit_width, u64 *value)
107 {
108 	acpi_status status;
109 	acpi_adr_space_handler handler;
110 	acpi_adr_space_setup region_setup;
111 	union acpi_operand_object *handler_desc;
112 	union acpi_operand_object *region_obj2;
113 	void *region_context = NULL;
114 	struct acpi_connection_info *context;
115 	acpi_mutex context_mutex;
116 	u8 context_locked;
117 	acpi_physical_address address;
118 
119 	ACPI_FUNCTION_TRACE(ev_address_space_dispatch);
120 
121 	region_obj2 = acpi_ns_get_secondary_object(region_obj);
122 	if (!region_obj2) {
123 		return_ACPI_STATUS(AE_NOT_EXIST);
124 	}
125 
126 	/* Ensure that there is a handler associated with this region */
127 
128 	handler_desc = region_obj->region.handler;
129 	if (!handler_desc) {
130 		ACPI_ERROR((AE_INFO,
131 			    "No handler for Region [%4.4s] (%p) [%s]",
132 			    acpi_ut_get_node_name(region_obj->region.node),
133 			    region_obj,
134 			    acpi_ut_get_region_name(region_obj->region.
135 						    space_id)));
136 
137 		return_ACPI_STATUS(AE_NOT_EXIST);
138 	}
139 
140 	context = handler_desc->address_space.context;
141 	context_mutex = handler_desc->address_space.context_mutex;
142 	context_locked = FALSE;
143 
144 	/*
145 	 * It may be the case that the region has never been initialized.
146 	 * Some types of regions require special init code
147 	 */
148 	if (!(region_obj->region.flags & AOPOBJ_SETUP_COMPLETE)) {
149 
150 		/* This region has not been initialized yet, do it */
151 
152 		region_setup = handler_desc->address_space.setup;
153 		if (!region_setup) {
154 
155 			/* No initialization routine, exit with error */
156 
157 			ACPI_ERROR((AE_INFO,
158 				    "No init routine for region(%p) [%s]",
159 				    region_obj,
160 				    acpi_ut_get_region_name(region_obj->region.
161 							    space_id)));
162 			return_ACPI_STATUS(AE_NOT_EXIST);
163 		}
164 
165 		if (region_obj->region.space_id == ACPI_ADR_SPACE_PLATFORM_COMM) {
166 			struct acpi_pcc_info *ctx =
167 			    handler_desc->address_space.context;
168 
169 			ctx->internal_buffer =
170 			    field_obj->field.internal_pcc_buffer;
171 			ctx->length = (u16)region_obj->region.length;
172 			ctx->subspace_id = (u8)region_obj->region.address;
173 		}
174 
175 		if (region_obj->region.space_id ==
176 		    ACPI_ADR_SPACE_FIXED_HARDWARE) {
177 			struct acpi_ffh_info *ctx =
178 			    handler_desc->address_space.context;
179 
180 			ctx->length = region_obj->region.length;
181 			ctx->offset = region_obj->region.address;
182 		}
183 
184 		/*
185 		 * We must exit the interpreter because the region setup will
186 		 * potentially execute control methods (for example, the _REG method
187 		 * for this region)
188 		 */
189 		acpi_ex_exit_interpreter();
190 
191 		status = region_setup(region_obj, ACPI_REGION_ACTIVATE,
192 				      context, &region_context);
193 
194 		/* Re-enter the interpreter */
195 
196 		acpi_ex_enter_interpreter();
197 
198 		/* Check for failure of the Region Setup */
199 
200 		if (ACPI_FAILURE(status)) {
201 			ACPI_EXCEPTION((AE_INFO, status,
202 					"During region initialization: [%s]",
203 					acpi_ut_get_region_name(region_obj->
204 								region.
205 								space_id)));
206 			return_ACPI_STATUS(status);
207 		}
208 
209 		/* Region initialization may have been completed by region_setup */
210 
211 		if (!(region_obj->region.flags & AOPOBJ_SETUP_COMPLETE)) {
212 			region_obj->region.flags |= AOPOBJ_SETUP_COMPLETE;
213 
214 			/*
215 			 * Save the returned context for use in all accesses to
216 			 * the handler for this particular region
217 			 */
218 			if (!(region_obj2->extra.region_context)) {
219 				region_obj2->extra.region_context =
220 				    region_context;
221 			}
222 		}
223 	}
224 
225 	/* We have everything we need, we can invoke the address space handler */
226 
227 	handler = handler_desc->address_space.handler;
228 	address = (region_obj->region.address + region_offset);
229 
230 	ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
231 			  "Handler %p (@%p) Address %8.8X%8.8X [%s]\n",
232 			  &region_obj->region.handler->address_space, handler,
233 			  ACPI_FORMAT_UINT64(address),
234 			  acpi_ut_get_region_name(region_obj->region.
235 						  space_id)));
236 
237 	if (!(handler_desc->address_space.handler_flags &
238 	      ACPI_ADDR_HANDLER_DEFAULT_INSTALLED)) {
239 		/*
240 		 * For handlers other than the default (supplied) handlers, we must
241 		 * exit the interpreter because the handler *might* block -- we don't
242 		 * know what it will do, so we can't hold the lock on the interpreter.
243 		 */
244 		acpi_ex_exit_interpreter();
245 	}
246 
247 	/*
248 	 * Special handling for generic_serial_bus and general_purpose_io:
249 	 * There are three extra parameters that must be passed to the
250 	 * handler via the context:
251 	 *   1) Connection buffer, a resource template from Connection() op
252 	 *   2) Length of the above buffer
253 	 *   3) Actual access length from the access_as() op
254 	 *
255 	 * Since we pass these extra parameters via the context, which is
256 	 * shared between threads, we must lock the context to avoid these
257 	 * parameters being changed from another thread before the handler
258 	 * has completed running.
259 	 *
260 	 * In addition, for general_purpose_io, the Address and bit_width fields
261 	 * are defined as follows:
262 	 *   1) Address is the pin number index of the field (bit offset from
263 	 *      the previous Connection)
264 	 *   2) bit_width is the actual bit length of the field (number of pins)
265 	 */
266 	if ((region_obj->region.space_id == ACPI_ADR_SPACE_GSBUS ||
267 	     region_obj->region.space_id == ACPI_ADR_SPACE_GPIO) &&
268 	    context && field_obj) {
269 
270 		status =
271 		    acpi_os_acquire_mutex(context_mutex, ACPI_WAIT_FOREVER);
272 		if (ACPI_FAILURE(status)) {
273 			goto re_enter_interpreter;
274 		}
275 
276 		context_locked = TRUE;
277 
278 		/* Get the Connection (resource_template) buffer */
279 
280 		context->connection = field_obj->field.resource_buffer;
281 		context->length = field_obj->field.resource_length;
282 		context->access_length = field_obj->field.access_length;
283 
284 		if (region_obj->region.space_id == ACPI_ADR_SPACE_GPIO) {
285 			address = field_obj->field.pin_number_index;
286 			bit_width = field_obj->field.bit_length;
287 		}
288 	}
289 
290 	/* Call the handler */
291 
292 	status = handler(function, address, bit_width, value, context,
293 			 region_obj2->extra.region_context);
294 
295 	if (context_locked) {
296 		acpi_os_release_mutex(context_mutex);
297 	}
298 
299 	if (ACPI_FAILURE(status)) {
300 		ACPI_EXCEPTION((AE_INFO, status, "Returned by Handler for [%s]",
301 				acpi_ut_get_region_name(region_obj->region.
302 							space_id)));
303 
304 		/*
305 		 * Special case for an EC timeout. These are seen so frequently
306 		 * that an additional error message is helpful
307 		 */
308 		if ((region_obj->region.space_id == ACPI_ADR_SPACE_EC) &&
309 		    (status == AE_TIME)) {
310 			ACPI_ERROR((AE_INFO,
311 				    "Timeout from EC hardware or EC device driver"));
312 		}
313 	}
314 
315 re_enter_interpreter:
316 	if (!(handler_desc->address_space.handler_flags &
317 	      ACPI_ADDR_HANDLER_DEFAULT_INSTALLED)) {
318 		/*
319 		 * We just returned from a non-default handler, we must re-enter the
320 		 * interpreter
321 		 */
322 		acpi_ex_enter_interpreter();
323 	}
324 
325 	return_ACPI_STATUS(status);
326 }
327 
328 /*******************************************************************************
329  *
330  * FUNCTION:    acpi_ev_detach_region
331  *
332  * PARAMETERS:  region_obj          - Region Object
333  *              acpi_ns_is_locked   - Namespace Region Already Locked?
334  *
335  * RETURN:      None
336  *
337  * DESCRIPTION: Break the association between the handler and the region
338  *              this is a two way association.
339  *
340  ******************************************************************************/
341 
342 void
acpi_ev_detach_region(union acpi_operand_object * region_obj,u8 acpi_ns_is_locked)343 acpi_ev_detach_region(union acpi_operand_object *region_obj,
344 		      u8 acpi_ns_is_locked)
345 {
346 	union acpi_operand_object *handler_obj;
347 	union acpi_operand_object *obj_desc;
348 	union acpi_operand_object *start_desc;
349 	union acpi_operand_object **last_obj_ptr;
350 	acpi_adr_space_setup region_setup;
351 	void **region_context;
352 	union acpi_operand_object *region_obj2;
353 	acpi_status status;
354 
355 	ACPI_FUNCTION_TRACE(ev_detach_region);
356 
357 	region_obj2 = acpi_ns_get_secondary_object(region_obj);
358 	if (!region_obj2) {
359 		return_VOID;
360 	}
361 	region_context = &region_obj2->extra.region_context;
362 
363 	/* Get the address handler from the region object */
364 
365 	handler_obj = region_obj->region.handler;
366 	if (!handler_obj) {
367 
368 		/* This region has no handler, all done */
369 
370 		return_VOID;
371 	}
372 
373 	/* Find this region in the handler's list */
374 
375 	obj_desc = handler_obj->address_space.region_list;
376 	start_desc = obj_desc;
377 	last_obj_ptr = &handler_obj->address_space.region_list;
378 
379 	while (obj_desc) {
380 
381 		/* Is this the correct Region? */
382 
383 		if (obj_desc == region_obj) {
384 			ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
385 					  "Removing Region %p from address handler %p\n",
386 					  region_obj, handler_obj));
387 
388 			/* This is it, remove it from the handler's list */
389 
390 			*last_obj_ptr = obj_desc->region.next;
391 			obj_desc->region.next = NULL;	/* Must clear field */
392 
393 			if (acpi_ns_is_locked) {
394 				status =
395 				    acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
396 				if (ACPI_FAILURE(status)) {
397 					return_VOID;
398 				}
399 			}
400 
401 			/* Now stop region accesses by executing the _REG method */
402 
403 			status =
404 			    acpi_ev_execute_reg_method(region_obj,
405 						       ACPI_REG_DISCONNECT);
406 			if (ACPI_FAILURE(status)) {
407 				ACPI_EXCEPTION((AE_INFO, status,
408 						"from region _REG, [%s]",
409 						acpi_ut_get_region_name
410 						(region_obj->region.space_id)));
411 			}
412 
413 			if (acpi_ns_is_locked) {
414 				status =
415 				    acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
416 				if (ACPI_FAILURE(status)) {
417 					return_VOID;
418 				}
419 			}
420 
421 			/*
422 			 * If the region has been activated, call the setup handler with
423 			 * the deactivate notification
424 			 */
425 			if (region_obj->region.flags & AOPOBJ_SETUP_COMPLETE) {
426 				region_setup = handler_obj->address_space.setup;
427 				status =
428 				    region_setup(region_obj,
429 						 ACPI_REGION_DEACTIVATE,
430 						 handler_obj->address_space.
431 						 context, region_context);
432 
433 				/*
434 				 * region_context should have been released by the deactivate
435 				 * operation. We don't need access to it anymore here.
436 				 */
437 				if (region_context) {
438 					*region_context = NULL;
439 				}
440 
441 				/* Init routine may fail, Just ignore errors */
442 
443 				if (ACPI_FAILURE(status)) {
444 					ACPI_EXCEPTION((AE_INFO, status,
445 							"from region handler - deactivate, [%s]",
446 							acpi_ut_get_region_name
447 							(region_obj->region.
448 							 space_id)));
449 				}
450 
451 				region_obj->region.flags &=
452 				    ~(AOPOBJ_SETUP_COMPLETE);
453 			}
454 
455 			/*
456 			 * Remove handler reference in the region
457 			 *
458 			 * NOTE: this doesn't mean that the region goes away, the region
459 			 * is just inaccessible as indicated to the _REG method
460 			 *
461 			 * If the region is on the handler's list, this must be the
462 			 * region's handler
463 			 */
464 			region_obj->region.handler = NULL;
465 			acpi_ut_remove_reference(handler_obj);
466 
467 			return_VOID;
468 		}
469 
470 		/* Walk the linked list of handlers */
471 
472 		last_obj_ptr = &obj_desc->region.next;
473 		obj_desc = obj_desc->region.next;
474 
475 		/* Prevent infinite loop if list is corrupted */
476 
477 		if (obj_desc == start_desc) {
478 			ACPI_ERROR((AE_INFO,
479 				    "Circular handler list in region object %p",
480 				    region_obj));
481 			return_VOID;
482 		}
483 	}
484 
485 	/* If we get here, the region was not in the handler's region list */
486 
487 	ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
488 			  "Cannot remove region %p from address handler %p\n",
489 			  region_obj, handler_obj));
490 
491 	return_VOID;
492 }
493 
494 /*******************************************************************************
495  *
496  * FUNCTION:    acpi_ev_attach_region
497  *
498  * PARAMETERS:  handler_obj         - Handler Object
499  *              region_obj          - Region Object
500  *              acpi_ns_is_locked   - Namespace Region Already Locked?
501  *
502  * RETURN:      None
503  *
504  * DESCRIPTION: Create the association between the handler and the region
505  *              this is a two way association.
506  *
507  ******************************************************************************/
508 
509 acpi_status
acpi_ev_attach_region(union acpi_operand_object * handler_obj,union acpi_operand_object * region_obj,u8 acpi_ns_is_locked)510 acpi_ev_attach_region(union acpi_operand_object *handler_obj,
511 		      union acpi_operand_object *region_obj,
512 		      u8 acpi_ns_is_locked)
513 {
514 
515 	ACPI_FUNCTION_TRACE(ev_attach_region);
516 
517 	/* Install the region's handler */
518 
519 	if (region_obj->region.handler) {
520 		return_ACPI_STATUS(AE_ALREADY_EXISTS);
521 	}
522 
523 	ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
524 			  "Adding Region [%4.4s] %p to address handler %p [%s]\n",
525 			  acpi_ut_get_node_name(region_obj->region.node),
526 			  region_obj, handler_obj,
527 			  acpi_ut_get_region_name(region_obj->region.
528 						  space_id)));
529 
530 	/* Link this region to the front of the handler's list */
531 
532 	region_obj->region.next = handler_obj->address_space.region_list;
533 	handler_obj->address_space.region_list = region_obj;
534 	region_obj->region.handler = handler_obj;
535 	acpi_ut_add_reference(handler_obj);
536 
537 	return_ACPI_STATUS(AE_OK);
538 }
539 
540 /*******************************************************************************
541  *
542  * FUNCTION:    acpi_ev_execute_reg_method
543  *
544  * PARAMETERS:  region_obj          - Region object
545  *              function            - Passed to _REG: On (1) or Off (0)
546  *
547  * RETURN:      Status
548  *
549  * DESCRIPTION: Execute _REG method for a region
550  *
551  ******************************************************************************/
552 
553 acpi_status
acpi_ev_execute_reg_method(union acpi_operand_object * region_obj,u32 function)554 acpi_ev_execute_reg_method(union acpi_operand_object *region_obj, u32 function)
555 {
556 	struct acpi_evaluate_info *info;
557 	union acpi_operand_object *args[3];
558 	union acpi_operand_object *region_obj2;
559 	const acpi_name *reg_name_ptr =
560 	    ACPI_CAST_PTR(acpi_name, METHOD_NAME__REG);
561 	struct acpi_namespace_node *method_node;
562 	struct acpi_namespace_node *node;
563 	acpi_status status;
564 
565 	ACPI_FUNCTION_TRACE(ev_execute_reg_method);
566 
567 	if (!acpi_gbl_namespace_initialized ||
568 	    region_obj->region.handler == NULL) {
569 		return_ACPI_STATUS(AE_OK);
570 	}
571 
572 	region_obj2 = acpi_ns_get_secondary_object(region_obj);
573 	if (!region_obj2) {
574 		return_ACPI_STATUS(AE_NOT_EXIST);
575 	}
576 
577 	/*
578 	 * Find any "_REG" method associated with this region definition.
579 	 * The method should always be updated as this function may be
580 	 * invoked after a namespace change.
581 	 */
582 	node = region_obj->region.node->parent;
583 	status =
584 	    acpi_ns_search_one_scope(*reg_name_ptr, node, ACPI_TYPE_METHOD,
585 				     &method_node);
586 	if (ACPI_SUCCESS(status)) {
587 		/*
588 		 * The _REG method is optional and there can be only one per
589 		 * region definition. This will be executed when the handler is
590 		 * attached or removed.
591 		 */
592 		region_obj2->extra.method_REG = method_node;
593 	}
594 	if (region_obj2->extra.method_REG == NULL) {
595 		return_ACPI_STATUS(AE_OK);
596 	}
597 
598 	/* _REG(DISCONNECT) should be paired with _REG(CONNECT) */
599 
600 	if ((function == ACPI_REG_CONNECT &&
601 	     region_obj->common.flags & AOPOBJ_REG_CONNECTED) ||
602 	    (function == ACPI_REG_DISCONNECT &&
603 	     !(region_obj->common.flags & AOPOBJ_REG_CONNECTED))) {
604 		return_ACPI_STATUS(AE_OK);
605 	}
606 
607 	/* Allocate and initialize the evaluation information block */
608 
609 	info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
610 	if (!info) {
611 		return_ACPI_STATUS(AE_NO_MEMORY);
612 	}
613 
614 	info->prefix_node = region_obj2->extra.method_REG;
615 	info->relative_pathname = NULL;
616 	info->parameters = args;
617 	info->flags = ACPI_IGNORE_RETURN_VALUE;
618 
619 	/*
620 	 * The _REG method has two arguments:
621 	 *
622 	 * arg0 - Integer:
623 	 *  Operation region space ID Same value as region_obj->Region.space_id
624 	 *
625 	 * arg1 - Integer:
626 	 *  connection status 1 for connecting the handler, 0 for disconnecting
627 	 *  the handler (Passed as a parameter)
628 	 */
629 	args[0] =
630 	    acpi_ut_create_integer_object((u64)region_obj->region.space_id);
631 	if (!args[0]) {
632 		status = AE_NO_MEMORY;
633 		goto cleanup1;
634 	}
635 
636 	args[1] = acpi_ut_create_integer_object((u64)function);
637 	if (!args[1]) {
638 		status = AE_NO_MEMORY;
639 		goto cleanup2;
640 	}
641 
642 	args[2] = NULL;		/* Terminate list */
643 
644 	/* Execute the method, no return value */
645 
646 	ACPI_DEBUG_EXEC(acpi_ut_display_init_pathname
647 			(ACPI_TYPE_METHOD, info->prefix_node, NULL));
648 
649 	status = acpi_ns_evaluate(info);
650 	acpi_ut_remove_reference(args[1]);
651 
652 	if (ACPI_FAILURE(status)) {
653 		goto cleanup2;
654 	}
655 
656 	if (function == ACPI_REG_CONNECT) {
657 		region_obj->common.flags |= AOPOBJ_REG_CONNECTED;
658 	} else {
659 		region_obj->common.flags &= ~AOPOBJ_REG_CONNECTED;
660 	}
661 
662 cleanup2:
663 	acpi_ut_remove_reference(args[0]);
664 
665 cleanup1:
666 	ACPI_FREE(info);
667 	return_ACPI_STATUS(status);
668 }
669 
670 /*******************************************************************************
671  *
672  * FUNCTION:    acpi_ev_execute_reg_methods
673  *
674  * PARAMETERS:  node            - Namespace node for the device
675  *              space_id        - The address space ID
676  *              function        - Passed to _REG: On (1) or Off (0)
677  *
678  * RETURN:      None
679  *
680  * DESCRIPTION: Run all _REG methods for the input Space ID;
681  *              Note: assumes namespace is locked, or system init time.
682  *
683  ******************************************************************************/
684 
685 void
acpi_ev_execute_reg_methods(struct acpi_namespace_node * node,acpi_adr_space_type space_id,u32 function)686 acpi_ev_execute_reg_methods(struct acpi_namespace_node *node,
687 			    acpi_adr_space_type space_id, u32 function)
688 {
689 	struct acpi_reg_walk_info info;
690 
691 	ACPI_FUNCTION_TRACE(ev_execute_reg_methods);
692 
693 	/*
694 	 * These address spaces do not need a call to _REG, since the ACPI
695 	 * specification defines them as: "must always be accessible". Since
696 	 * they never change state (never become unavailable), no need to ever
697 	 * call _REG on them. Also, a data_table is not a "real" address space,
698 	 * so do not call _REG. September 2018.
699 	 */
700 	if ((space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY) ||
701 	    (space_id == ACPI_ADR_SPACE_SYSTEM_IO) ||
702 	    (space_id == ACPI_ADR_SPACE_DATA_TABLE)) {
703 		return_VOID;
704 	}
705 
706 	info.space_id = space_id;
707 	info.function = function;
708 	info.reg_run_count = 0;
709 
710 	ACPI_DEBUG_PRINT_RAW((ACPI_DB_NAMES,
711 			      "    Running _REG methods for SpaceId %s\n",
712 			      acpi_ut_get_region_name(info.space_id)));
713 
714 	/*
715 	 * Run all _REG methods for all Operation Regions for this space ID. This
716 	 * is a separate walk in order to handle any interdependencies between
717 	 * regions and _REG methods. (i.e. handlers must be installed for all
718 	 * regions of this Space ID before we can run any _REG methods)
719 	 */
720 	(void)acpi_ns_walk_namespace(ACPI_TYPE_ANY, node, ACPI_UINT32_MAX,
721 				     ACPI_NS_WALK_UNLOCK, acpi_ev_reg_run, NULL,
722 				     &info, NULL);
723 
724 	/*
725 	 * Special case for EC and GPIO: handle "orphan" _REG methods with
726 	 * no region.
727 	 */
728 	if (space_id == ACPI_ADR_SPACE_EC || space_id == ACPI_ADR_SPACE_GPIO) {
729 		acpi_ev_execute_orphan_reg_method(node, space_id);
730 	}
731 
732 	ACPI_DEBUG_PRINT_RAW((ACPI_DB_NAMES,
733 			      "    Executed %u _REG methods for SpaceId %s\n",
734 			      info.reg_run_count,
735 			      acpi_ut_get_region_name(info.space_id)));
736 
737 	return_VOID;
738 }
739 
740 /*******************************************************************************
741  *
742  * FUNCTION:    acpi_ev_reg_run
743  *
744  * PARAMETERS:  walk_namespace callback
745  *
746  * DESCRIPTION: Run _REG method for region objects of the requested spaceID
747  *
748  ******************************************************************************/
749 
750 static acpi_status
acpi_ev_reg_run(acpi_handle obj_handle,u32 level,void * context,void ** return_value)751 acpi_ev_reg_run(acpi_handle obj_handle,
752 		u32 level, void *context, void **return_value)
753 {
754 	union acpi_operand_object *obj_desc;
755 	struct acpi_namespace_node *node;
756 	acpi_status status;
757 	struct acpi_reg_walk_info *info;
758 
759 	info = ACPI_CAST_PTR(struct acpi_reg_walk_info, context);
760 
761 	/* Convert and validate the device handle */
762 
763 	node = acpi_ns_validate_handle(obj_handle);
764 	if (!node) {
765 		return (AE_BAD_PARAMETER);
766 	}
767 
768 	/*
769 	 * We only care about regions and objects that are allowed to have
770 	 * address space handlers
771 	 */
772 	if ((node->type != ACPI_TYPE_REGION) && (node != acpi_gbl_root_node)) {
773 		return (AE_OK);
774 	}
775 
776 	/* Check for an existing internal object */
777 
778 	obj_desc = acpi_ns_get_attached_object(node);
779 	if (!obj_desc) {
780 
781 		/* No object, just exit */
782 
783 		return (AE_OK);
784 	}
785 
786 	/* Object is a Region */
787 
788 	if (obj_desc->region.space_id != info->space_id) {
789 
790 		/* This region is for a different address space, just ignore it */
791 
792 		return (AE_OK);
793 	}
794 
795 	info->reg_run_count++;
796 	status = acpi_ev_execute_reg_method(obj_desc, info->function);
797 	return (status);
798 }
799 
800 /*******************************************************************************
801  *
802  * FUNCTION:    acpi_ev_execute_orphan_reg_method
803  *
804  * PARAMETERS:  device_node         - Namespace node for an ACPI device
805  *              space_id            - The address space ID
806  *
807  * RETURN:      None
808  *
809  * DESCRIPTION: Execute an "orphan" _REG method that appears under an ACPI
810  *              device. This is a _REG method that has no corresponding region
811  *              within the device's scope. ACPI tables depending on these
812  *              "orphan" _REG methods have been seen for both EC and GPIO
813  *              Operation Regions. Presumably the Windows ACPI implementation
814  *              always calls the _REG method independent of the presence of
815  *              an actual Operation Region with the correct address space ID.
816  *
817  *  MUTEX:      Assumes the namespace is locked
818  *
819  ******************************************************************************/
820 
821 static void
acpi_ev_execute_orphan_reg_method(struct acpi_namespace_node * device_node,acpi_adr_space_type space_id)822 acpi_ev_execute_orphan_reg_method(struct acpi_namespace_node *device_node,
823 				  acpi_adr_space_type space_id)
824 {
825 	acpi_handle reg_method;
826 	struct acpi_namespace_node *next_node;
827 	acpi_status status;
828 	struct acpi_object_list args;
829 	union acpi_object objects[2];
830 
831 	ACPI_FUNCTION_TRACE(ev_execute_orphan_reg_method);
832 
833 	if (!device_node) {
834 		return_VOID;
835 	}
836 
837 	/* Namespace is currently locked, must release */
838 
839 	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
840 
841 	/* Get a handle to a _REG method immediately under the EC device */
842 
843 	status = acpi_get_handle(device_node, METHOD_NAME__REG, &reg_method);
844 	if (ACPI_FAILURE(status)) {
845 		goto exit;	/* There is no _REG method present */
846 	}
847 
848 	/*
849 	 * Execute the _REG method only if there is no Operation Region in
850 	 * this scope with the Embedded Controller space ID. Otherwise, it
851 	 * will already have been executed. Note, this allows for Regions
852 	 * with other space IDs to be present; but the code below will then
853 	 * execute the _REG method with the embedded_control space_ID argument.
854 	 */
855 	next_node = acpi_ns_get_next_node(device_node, NULL);
856 	while (next_node) {
857 		if ((next_node->type == ACPI_TYPE_REGION) &&
858 		    (next_node->object) &&
859 		    (next_node->object->region.space_id == space_id)) {
860 			goto exit;	/* Do not execute the _REG */
861 		}
862 
863 		next_node = acpi_ns_get_next_node(device_node, next_node);
864 	}
865 
866 	/* Evaluate the _REG(space_id,Connect) method */
867 
868 	args.count = 2;
869 	args.pointer = objects;
870 	objects[0].type = ACPI_TYPE_INTEGER;
871 	objects[0].integer.value = space_id;
872 	objects[1].type = ACPI_TYPE_INTEGER;
873 	objects[1].integer.value = ACPI_REG_CONNECT;
874 
875 	(void)acpi_evaluate_object(reg_method, NULL, &args, NULL);
876 
877 exit:
878 	/* We ignore all errors from above, don't care */
879 
880 	(void)acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
881 	return_VOID;
882 }
883